Neck Pain - Dx and Tx

Practical Questions

How do you know if your patient's radiating pain is radicular (nerve root)?

What is scleratogenous pain?

What is the evidence for manipulation and exercise?

Is it safe to use manipulation for cervical radiculopathy?

Is manipulation an effective treatment approach for cervical radiculopathy?

At what point do I refer?

Causes of Neck Pain

Similar to low back pain, the pain generator for neck pain is difficult to pinpoint.

It is clear that by the time a patient reaches the age of 40, the nucleus pulposus is essentially non-existent having turned into a ligamentous-like, dry material.

When pain radiates into the arm from the neck, two clear possibilities exist: (1) nerve root, and (2) scleratogenous pain from deep structures such as the disc (non-herniated), facet joints, deep ligaments and muscles.

Nerve root involvement is primarily from foraminal encroachment (80% of the time) versus disc (20% of the time).

Important Diagnostic Tests and Their Value

Ortho Testing for Cervical Radiculopathy (CR)

Classic belief is that patients with CR have:

Decreased or absent DTR(s)

Loss of sensation (dermatome)

Myotome weakness

However, testing is highly specific but very poor in sensitivity. In other words, the patient may have a bony impingement or disc lesion compressing or irritating a nerve root and NOT have a positive neurological finding.

The Best Cluster for Cervical Radiculopathy

The literature suggests that the best tests are a cluster including:

Upper limb tension test

Restricted cervical rotation < 60 degrees

Distraction (relieving radiating pain)

Spurling’s (aggravating radiating pain)

History questions and standard neurological evaluation were not sensitive

Manipulation in the Management of Cervical Radiculopathy

Manipulation of patients with cervical disc-related radiculopathy has been viewed by the medical profession as a risky management approach. Also the literature evidence for success with manipulation for patients with radiculopathy has until recently been summarized as insufficient. A current study is the first step in demonstrating the safety and success of a high-velocity, low-amplitude adjusting approach for patients with MRI-documented disk-related cervical radiculopathy.

The results were impressive with participants reporting being better or much better in the following percentages. At 2 Weeks: 55%, at 1 Month: 69% and at 3 Months: 86%. Reductions in NRS neck and arm pain scores as well as the NDI scores at 3 months were approximately between 66% and 75%

A higher proportion of acute (< 4 weeks) patients improved faster than those who were sub-acute or chronic

Compared to the results of a recent study using 2 cervical nerve root blocks consisting of a corticosteroid and anesthetic researchers reported only 24% of these patients (5/21) had clinically relevant reduction in their symptoms which translates into only a 25% reduction in their NRS score, at 6 weeks and 4 months after injection

Based on the results of this current study and previous studies, patients with radiculopathy are not only safely managed using HVLA but also experience improvement whether acute or chronic.

JMPT 2013 - Peterson et al.

2014 – What is known about strain forces on the cervical spine with manipulation?

Due to the rarity of VBA, the evidence needed for a defense for or against a cause-and-effect relationship between cervical manipulation and stroke can never be known. Yet the basic science evidence regarding the feasibility that cervical manipulation forces are high enough to cause damage can be simulated and studied using cadavers. The results of several studies by Herzog, et al are presented here as one component of a defense for the safety of cervical manipulation.

Peak force for cervical manipulation is 200 N (44 lbs)

Thrust speed is consistent at about 100–200 ms

Forces applied are similar for:

Male vs female clinicians and,

Patients vs non-patients in lab settings

The current evidence suggests that damage is unlikely for the distal extra-cranial loop of the VA (between C1 and the foramen magnum)and the loop between C6 and the VA's origin from the subclavian artery

At V1 strains are about twice that for SMT versus ROM, whereas at V4, it is the opposite with ROM testing strains at three times that of SMT strains. That being said, the largest strain forces were still at their highest only 6.2%

At V1, V2, and V3, ROM testing in one study always produced higher strain forces than SMT by at least three times and that strain increases from V1 to V3. Still the highest strain even for ROM testing is only about 12%

Microdamage due to repeated strain from multiple manipulations over time has been proposed as a possible underlying cause. A recent study, tested this theory through a number of loading cycles and there was no damage at 6% strain but 1000 cycles of 30% strain caused significant microstructural damage to the arterial tissue. But according to the available literature SMT strains range from only 0.9–6.2%!.The mean failure strain of the internal carotid artery in the reviewed study was 59% (± 16%).

Similar to vertebral artery testing, ROM testing strains were significantly greater than the corresponding maximal strains for the SMTs

The mean of all maximal ICA strains obtained with SMTs was 28% of that measured during the ROM testing and was only 10% of the failure strain of the ICA.

Of course, some chiropractors and others who perform manipulations may use excessive rotary or stretching forces that were not captured by these studies, however, it must be assumed that the vast majority of practitioners use the types of adjustments simulated in this study and use caution.

What we can say is that it is far less likely than casually assumed that the forces of manipulation are damaging and in fact are likely similar to those of daily movement. Also, repeated movement similar to these simulated adjustments with repeated use in the same patient with reasonable, standardized application, does not cause damage.

Manipulation based on basic science, is a relatively safe procedure when compared to other approaches to neck pain and headache